Pumpkin seed protein nanoparticles, methods for preparing and using thereof
The present invention provides a method for preparing an high internal phase of pumpkin seed protein nanoparticles, including dissolving pumpkin seed protein powder in water and adjusting pH to approximately 8 to 11 to obtain a pumpkin seed protein solution; adding the pumpkin seed protein solution through a peristaltic pump into an ethanol solution with stirring for 4 hours to obtain a first solution; performing a centrifugation to the first solution and collecting precipitates; diluting the precipitates with water and performing a freeze-drying to obtain the pumpkin seed protein nanoparticles. The present invention first uses an anti-solvent method to prepare pumpkin seed protein nanoparticles, which have excellent emulsifying properties and can stabilize the high internal phase emulsion. In addition, the resulting pumpkin seed protein nanoparticles can stabilize the high internal phase emulsion independently without compounding with other substances.
1. A method for preparing a high internal phase emulsion of pumpkin seed protein nanoparticles, comprising:
dissolving pumpkin seed protein powders in water and adjusting pH to approximately 8 to 11 to obtain a pumpkin seed protein solution;
adding the pumpkin seed protein solution through a peristaltic pump into an ethanol solution with stiffing for 4 hours to obtain a first solution;
performing a centrifugation to the first solution and collecting precipitates;
diluting the precipitates with water and performing a freeze-drying to obtain the pumpkin seed protein nanoparticles;
dispersing the pumpkin seed protein nanoparticles in water in an amount of approximately 1.5 to 2% w/v to obtain a pumpkin seed protein nanoparticles solution;
adding an essence to the pumpkin seed protein nanoparticles solution in an amount of approximately from 80 to 82% w/v, maintaining pH at approximately 3, 8 or 9 and performing a high speed shearing under 12000 rpm in a homogenizer to obtain a high internal phase emulsion containing the essence; and
wherein the concentration of the pumpkin seed protein in the pumpkin seed protein solution is approximately from 5 to 15 mg/ml;
wherein the ethanol solution is an anhydrous ethanol solution and the mass ratio of the ethanol solution to the pumpkin seed protein solution is approximately 3:1.
2. The method of claim 1 , wherein the peristatic pump for said adding the pumpkin seed protein solution into the ethanol solution has a flow rate of approximately 1.25 to 5 ml/min.
3. The method of claim 1 , wherein the centrifugation to the first solution is performed at approximately 4500 rpm for approximately 6 minutes.
4. The method of claim 1 , wherein the mass ratio of the water to the precipitates in said diluting the precipitates with the water is approximately 10:1.
5. The method of claim 1 , wherein the freeze-drying temperature of said performing the freeze-drying is approximately −50° C. and the drying time is approximately 3 days.
6. The method of claim 1 , wherein the average particle size of the pumpkin seed protein nanoparticles is approximately from 150 to 320 nm.